1. Field of the Invention
The present invention generally relates to a socket connector, and in particular to a trifurcated contact element of a socket connector for providing a reliable electrical engagement with a solder ball of an integrated circuit (IC) module.
2. The Prior Art
Ball grid array (BGA) socketing technique is well known in the electronics field. An IC module has a number of pins each having a solder ball attached thereto. A socket connector defines a number of contact chambers each retaining a contact element therein. The solder balls of the IC module are received in the chambers and form electrical engagement with the contact elements. The contact elements may be single finger members each having a single portion engaging with the solder ball or multiple finger members each having at least two portions engaging with the solder ball. U.S. Pat. Nos. 5,641,945, 5,702,255 and 5,730,606 and Taiwan Patent Application No. 85108360 disclose conventional BGA socketing systems.
The single finger contact of the conventional BGA socketing system does not provide reliable engagement with the solder ball of the IC module. In addition, the conventional multiple finger contact is complicated in structure and requires a sophisticated manufacturing process, leading to high costs. Furthermore, an oxidation layer is usually formed around the solder ball which increases the electrical impedance between the solder ball and the corresponding contact of the socket connector. The conventional BGA socketing system provides no means to overcome such a problem.
It is thus desired to have a BGA socket connector which overcomes the problems discussed above.